Washington (IAD) to Los Angeles (LAX): On-Time Performance
Data through May 2026
The calendar drives reliability on IAD–LAX. September 2024 flights landed on schedule 92% of the time, but July 2025 dropped to 60% — a gap of 32 points. Across the full period the route averages 83% on-time against a national 78%. Morning departures also hold up better than evening ones (90% vs 76%), which matters most in the rough months.
- On-time
- 83%
- arrived <15 min late
- Avg delay
- 13 min
- completed flights
- Cancelled
- 0.7%
- Flights/day
- 6.6
- last 12 months
- Duration
- 5h 41m
- scheduled
- Distance
- 2,288 mi
Best airline from IAD to LAX
2 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 84% | 12 min | 0.7% | 4,536 |
| Alaska Airlines | 73% | 19 min | 0.2% | 476 |
Monthly on-time trend
Best time to fly from IAD to LAX
Aim for departures around 7 a.m. (93% on-time); avoid 8 p.m. departures (68%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 84% | 12 min |
| Tuesdaybest | 86% | 10 min |
| Wednesday | 83% | 10 min |
| Thursday | 80% | 15 min |
| Friday | 84% | 13 min |
| Saturday | 82% | 11 min |
| Sunday | 80% | 16 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft35%
- Airline operations35%
- National airspace system20%
- Weather10%
Frequently asked questions
- How often are flights from IAD to LAX delayed?
- 17% of IAD–LAX flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 13 minutes.
- Which airline is most reliable from IAD to LAX?
- United Airlines has the best on-time record on this route at 84%, based on 4,536 flights. 2 airlines flew IAD–LAX frequently enough to compare in this period.
- What is the best time of day to fly from IAD to LAX?
- Departures around 7 a.m. have the best record (93% on-time), while departures around 8 p.m. have the worst (68%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from IAD to LAX?
- The scheduled IAD–LAX flight time averages 5h 41m over 2,288 miles. Actual arrival times vary — flights on this route land 15+ minutes late 17% of the time.
- How often are IAD to LAX flights cancelled?
- 0.7% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from IAD to LAX?
- July 2025 was the roughest month in this dataset, with only 60% of arrivals on time. The best was September 2024 at 92%. If your dates are flexible, that 32-point gap is worth planning around.
Explore related pages
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Based on 5,066 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.